Starter for internal-combustion engines



Jan. 12, 1954 TROEGER Q 2,665,587

STARTER FOR INTERNAL-COMBUSTION ENGINES Filed April 27, 1951 N 'S 8l h a\ K! a a n N g] m 3 INVENTOR.

HENRY TROEGER BY Patented Jan. 12,1954

Henry Tro'eger, Ramsey, N; 3.; assignor to Bendix Aviation- Corporation, Teterbo'ro N. J.; a corporation'of Delaware s piicatm'espril 27, 1951, Serial No. 222,365

The presentinvention' relates to engine starters and'particularlyto Starter jaw advancing mechanism.

in engine starters itis desirable to have some method of automatically advancing the starterjaw into mesh with the engine jaw. One method which has been used comprises a nut, driven by tion ring results in a loss of efficiency anda deerease of effectiveness of the jaw advance mechanism as the friction reduces due to wear in service. Another disadvantage is that the nut and s'crewshaft arelocated after the reduction gear- I ring which requires that they be large enough to have sufficient strength for handling the high screw shaft is to advance the jaw which requires a relatively small force. Hence, it could be a smaller mechanism if located in a'more favorable position. e V y In the present invention, the starter jaw is I'r'i'eshed by a cam action ahead of thereduction gearing". High starting torque cannot be applied until the jaw teeth are fully meshed. Also, the advancement of the starter jaw is rapid, thus preventing high impact loads due to high armature speeds as are obtained in other methods.

An object of the present invention is to provide an improved starter.

Another object of the invention is to provide improved jaw meshing mechanism.

Another object of the invention is to provide novel positive jaw actuating mechanism.

Another object is to provide a jaw advancing 1 mechanism in which fewer smaller and. simpler parts are required.

Anotherobjct or the invention is to provide a relative-y w cost r'lgili' starter.

The above and other objects and features of the invention will appear more fully hereinafter from a consideration of the following description taken in connection with the accompanying drawings wherein one embodiment of the invention is illustrated by way of example.

In the drawing:

The single figure of the drawing is a partial section view of an engine starter embodying one form of the invention.

Referring to the drawing, the device therein 3 Claims. (G1. 74-9) torque required for starting. The purpose of the shown comprises a starter assembly mam-dine, in

generm, a motor'l, having a driving shaft 2 retatably supported by a scanner mounted in end wall 4 of motor housing 5. The shaft 2 has a counterbore portion 6 adapted to receive an enlarged portion 1 of'a shaft .8. A helical cam9 is formed in the enlarged-portion i of the shaft 8. A pin it secured to the driving shaft 2 extends into the helical cam 9.

The shaft 8 has "a pinion gear ll integral therewith. The gear I! meshes with planetary gear 52. The gear I2 is carried by 'a'sh'aft I3 mounted in p ahet y case M. The shaft i3 is secured in the cage M by a pin '15 or ih'any other suitable manner. A wall It 6f gear housing I! has a circumferential sense 18 for pos tioning the cage M. A bearing member l9 may be positioned between the cage [4' "and the fia 18. The gear I2 is adapted to mesh with a ring gear 29 secured against rotatiori'to' the housing H in any suitable manner,

Integral with the gear 12 is a gear 2! adapted to mesh with splines 22 of barrel 23. The barrel 23 is rotatably mounted in the housing I1. The inner surface or the housing 11 and outer surface of the barrel 23 are finished to" provide bearing surfaces. I t is understood, however, that :the barrel 23 could be ifioiihtd'ifi' the housing [1 by other bearing means. U v

, The barrel 23 is co'riii'ected te starter jaw 24 by a clutch pac et. The clutch pack 25 has one set of discs 26 splined to the barrel 23 and another set of discs 21 s'li'dably splined to the jaw 24. Pressure is applied to the-clutch pack 25 by means of a spring 28 whicli'iiiay be a belle ville washer. stacking plate '29 is secured in position by asriap ring so pieced groove 3| in the barrel 23'. v i v y A bearing support 32 is hem against a shoulder 33 in the barrel 23 by the reaction 'of the spring 28. The bearing support 3'2 has a cylindrical portion'ss extending into couiiterbere portion 35 of jaw 24. A bearing 36' piloted by. and is free to moveaxiauy theylindrial portion at. A shank portion of shaft 8 is secured to the bearing 35 by a shoulder 3'! on the shaft 8 and a lock ring 38.

A mesh rod 39 extends axially of the counterbore portion 35 and extends through the jaw 24. A nut 49 retains the jaw 24 in operative relationship with the mesh rod 39. The other end of the rod 39 terminates in a flanged portion 4| which pilots in the cylindrical portion 34. A spring 42 positioned between the flange 4| and the jaw 24 urges the jaw 24 into engagement with an engine jaw (not shown) upon being compressed by movement of the mesh rod 39.

A spring 43 positioned between the flange 4i and a radially extending flange 44 on the cylindrical portion 35 serves to return the jaw 24 to a retracted position.

The housings 5 and H are secured together by bolts 45. The housing IT has an outward extending flange 46 adapted to be secured to an engine housing 41 in a conventional manner, for example, by studs 48. An end cover 49 is secured to the housing I! by the bolts 45.

In operation, upon the motor I being energized, the acceleration of the armature shaft 2 will cause a torque to be applied to the shaft 8 through the pin H). The inertia of the parts, comprising the reduction gearing, barrel, clutch and jaw, will cause the pin ill to exert an axial thrust on the cam surface 9. This axial thrust due to the lead of the cam surface 9 will cause the shaft 8 to move axially and thereby move the bearing 36 axially in the bearing support 32. Movement of the bearing 35 causes a corresponding movement of the mesh rod 39 which compresses the spring 42. The spring 42 upon being compressed urges the starter jaw 24 into engagement with the engine jaw (not shown).

If th starter and engine jaw teeth mesh at partial depth, no appreciable torque can be applied until the cam 9 has fully advanced on the pin Hi. This insures full engagement of starter and engine jaw teeth. Upon cranking an engine, should the engine jaw accelerate and push the starter jaw out of mesh, the release of the torque load from the motor will permit the armature to accelerate thus re-engaging the jaws as in initial starting.

Upon the starter being deenergized, the de celeration of the armature will tend to retract the jaws by the action of the pin ill upon the cam surface 9 in a reverse manner from that of acceleration of the armature. This avoids or reduces the ratcheting of the starter and engine jaw teeth which normally occurs when friction means are used for jaw advancement and the armature coasts to a stop.

The meshing spring 42 limits the axial force that can be applied to the jaw upon contact between the jaws and also permits the engine jaw to overrun the starter jaw. The jaw return spring 43 exerts a smaller retraction force on the jaw than is available for jaw advancement when starting, but is sufficient to insure retraction of the jaw regardless of the position in which the starter is mounted.

of the parts may be made to suit requirements.

What is claimed is:

1. An engine starter comprising driving means, a pinion shaft, means including a cam connection for connecting said shaft for rotation with and axial movement relative to said driving means, a rotatable barrel member, reduction gearing interconnecting said barrel member and said pinion shaft, a starter jaw member, a splined clutch pack for connecting said starter jaw for rotation with and axial movement relative to said barrel member, and means responsive to axial movement of said shaft for urging said starter jaw to an extended position.

2. In an engine starter, the combination of driving means having a driving member, a pinion shaft having a pinion gear integral therewith, cam means for connecting said pinion shaft for rotation with and axial movement relative to said driving member, said cam means being responsive to initial rotation of said driving means to cause said axial movement, a rotatable barrel member, reduction gearing connecting said pinion gear and said barrel member, a starter jaw member, a spring biased clutch pack connecting said starter jaw to said barrel member for rotation with and axial movement relative thereto, and yieldable means responsive to axial movement of said pinion shaft for urging said starter jaw to an engine engaging position.

3. In an engine starter, the combination of driving means, a rotatable axially movable pinion shaft having a spiral cam groove formed in one end thereof, a pin member secured to said driving means and adapted for register in said cam groove, a rotatable barrel member, reduction gearing connecting said pinion shaft and said barrel member, a starter jaw member, a spring biased clutch pack for connecting said jaw member for rotation with and splined for axial movement relative to said barrel member, a mesh rod member adapted for axial movement by said pinion shaft, spring means interposed between said mesh rod member and said jaw member for urging said jaw member into an engaging position upon actuation of said mesh rod member, said pin member coacting with said cam groove to move said pinion shaft axially and to provide a driving connection between said driving means and said shaft.

HENRY TROEGER.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,151,439 Brooks et al Aug. 24, 1915 1,868,346 Chilton July 19, 1932 FOREIGN PATENTS Number Country Date 451,125 Great Britain July 30, 1936 541,765 Great Britain Dec. 10, 1941 948,431 France Jan. 31, 1949 

